Cache of the valid channel name regex

* Added a Benchmark to verify the performance
* Now it is 10 times faster

Makefile

@@ -7,7 +7,7 @@ run-debug: debug
 	${GOPATH}/bin/ipe --config ${GOPATH}/src/github.com/dimiro1/ipe/config.json -logtostderr=true -v=2
 
 test:
-	GO15VENDOREXPERIMENT=1 go test `go list ./... | grep -v vendor`
+	GO15VENDOREXPERIMENT=1 go test -bench . `go list ./... | grep -v vendor | grep -v functional | grep -v github.com/dimiro1/ipe$$`
 
 dev-deps:
 	go get github.com/pusher/pusher-http-go

utils/utils.go

@@ -14,6 +14,12 @@ import (
 	"regexp"
 )
 
+var validChannelName *regexp.Regexp
+
+func init() {
+	validChannelName = regexp.MustCompile("^[A-Za-z0-9_\\-=@,.;]+$")
+}
+
 // HashMAC Calculates the MAC signing with the given key and returns the hexadecimal encoded Result
 func HashMAC(message, key []byte) string {
 	mac := hmac.New(sha256.New, key)
@@ -25,18 +31,10 @@ func HashMAC(message, key []byte) string {
 
 // GenerateSessionID Generate a new random Hash
 func GenerateSessionID() string {
-	MAX := math.MaxInt64
+	return fmt.Sprintf("%d.%d", rand.Intn(math.MaxInt64), rand.Intn(math.MaxInt64))
-
-	return fmt.Sprintf("%d.%d", rand.Intn(MAX), rand.Intn(MAX))
 }
 
 // IsChannelNameValid Verify if the channel name is valid
 func IsChannelNameValid(channelName string) bool {
-	matched, err := regexp.MatchString("^[A-Za-z0-9_\\-=@,.;]+$", channelName)
+	return validChannelName.Match([]byte(channelName))
-
-	if err == nil && matched {
-		return true
-	}
-
-	return false
 }

utils/utils_test.go

@@ -9,6 +9,18 @@ import (
 	"testing"
 )
 
+func BenchmarkGenerateSession(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		GenerateSessionID()
+	}
+}
+
+func BenchmarkIsChannelNameValid(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		IsChannelNameValid("hello-world")
+	}
+}
+
 func TestGenerateSession(t *testing.T) {
 	sessionID := GenerateSessionID()